View Full Version : Calling all electrical gurus

10-16-2003, 08:37 PM
We are in the process of cutting an 8 x 16 double sided sign. The left halve of each side has 5 files. The right side has 6 files. At this point we have completed 1 left and 1 right. All files cut as they should except the 2 files that cleared the recessed portion. Both of these files lost the 0 location on the x axis during the cut. One was off by 1/4 the other off by 7/16. While each of these files was cutting, and only on these 2 files I cleared the table off with an (very) old electric leaf blower. Thinking back to doing this I realize that I was probably very close to the x motor on the left side of the table. Is it possible that static from the blower fed back to the contol box. If so is it possible for this to happen when the machine is simply on but not cutting.

In addition, I just had to replace that motor (something I was told is extremly rare). The table is always blown off from that side. Is it possible that 2 years of exposure to a leaf blower could actually ruin a stepper motor. I will not be able to respond or even read your responses until Monday so don't get upset and think your help is being ignored.

Headed for the woods Frank

10-16-2003, 09:29 PM
Frank send me your files if you can and I will have alook at them and see if there is anything peculiar there.

And The Leaf blower should not be a hiccup, I used compressed air to clear my table all the time.

10-17-2003, 11:39 AM
I also used compressed air to clear the table.....but to the more important subject. I'm going to hazard a guess here. You did not mention the size of your table, but, from the size of the sign you mentioned, I'm betting you very possibly overshot your table limits slightly in one direction (x) and lost some steps on your (x)stepper motor(s). This would of course, cause 0,0 to move from it's original position. If this is the case, be sure and check your table for square after resetting the coordinates.....D

10-17-2003, 12:02 PM
Frank... have you tried running the files again? If the problem occurs every time, then check your part files for errors. Are your files written to reference in absolute distance or relative distance? If in absolute, make sure that the "SA" command is inserted at the beginning of each file.
If it only happened once then there are some obvious things to look at. 1st: Is the leaf blower on the same AC circuit as the controller? If so, use a different circuit for each. If that is not an option, use an UPS/power conditioner on your controller/driver computer. This with help protect against spikes, surges, sags, dirty power, etc. 2nd: Electric motors can generate a tremendous amount of RF as well as strong electro-magnetic fields. These can very easily interfere with line level signals. It is conceivable that it caused a hiccup. Consider an alternate chip clearing method. -Jim

10-18-2003, 09:53 PM
Hi Frank,
I had the same problem using my shopvac -- static from the plastic hose and nozzle. I now turn the motors off (using the "MO" or "M0") command and haven't had a problem since.

10-20-2003, 08:56 AM
Thanks for your replies guys. Just finished an air cut of the right halve clear recess file an 0,0 did not change. I don't know that this proves the brushes in the electric leaf blower caused the problem but it did eliminate a lot of other possibilities. Am still wondering if this could have contributed to the motor failure.
Thanks again